Table of contents

In this study, the researchers explored 10th
grade-students' understanding of molecular genetics, focusing on genes as
physical entities, but also as packets of information. The authors argue that students struggle
with this information for three reasons: the concepts are inaccessible to the
students because they are sub-cellular, the concepts are spread across many
biological levels, and that multiple molecules are key players that also span
many hierarchical levels. They assessed the students using written
assessment and interviews before and after instruction. What I liked about their assessment
tools is they used open-ended questions that avoided "false
positives" for misconceptions -- a problem outlined in Jenny's reference,
Clerk and Rutherford (2000). They
focused their interviewing on the relationship between genes and proteins, but
their methods and many of their questions could be expanded to include the
relationships between genes, chromosomes and DNA. While they identify some interesting misconceptions they did
not explore the source of those misconceptions. Are they a lack of background (and so not really a
misconception -- just a lack of any understanding)? Or are they caused by something in previous coursework or
popular media? I would like to
expand on their work and include the source of these alternative conceptions.

While most studies I have read have been conducted
on a specific grade level, this research spans early high school, late high
school, college and post-degree, pre-service teachers. Students were assessed on their
understanding of molecular genetics using open-ended questions on written
questionnaires and verbal interviews as well as concept maps (see more below in
3b). They received fascinated
results.Students at all levels
compartmentalized their definitions of "genes", "DNA" and
"Chromosomes" as either structural (chromosomes) OR functional (genes
and DNA), but not both. If the
definition was functional, terms were made distinct even though, in reality,
they have similar functions. For
example, genes "determine traits" and DNA "transfers hereditary
information from one generation to the next". The conclusion of the study was that students at all levels
fail to make many connections, both structural and functional, required for a
full-picture understanding of molecular genetics.

Many students claim, correctly or not, that they are
visual learners.Both these papers
use visual tools to facilitate and assess student learning. I like the first paper because the
authors present a drawing-based learning activity that encourages students to
analyze, complete and replicate figures commonly found in biology
textbooks. The upper-level
high-school students were assessed on their understanding of molecular genetics
after the activity and their scores and learning attitudes were compared with a
control group who received traditional instruction. The researchers found that the visual tools increased
student performance on the post-instructional assessment. In the second paper, biology majors
were given an introduction to concept maps and asked to create a concept map of
various terms in molecular genetics. The researchers then used the concept map as a tool to assess student
understanding of the concepts. By using
this assessment technique the researchers were able to uncover several
misconceptions that were previously unidentified by the instructor.

I included these papers for two reasons. First, some of their assessment methods
using drawing or concept maps could be used in my assessment. Second, someday I hope to develop
instructional methods that target these misconceptions and the techniques
presented in these papers may be a good place to start.

I have previously conducted research in my
classroom on student understand of molecular genetics, but the assessment tool
we used (mostly multiple choice) failed to assess how sure students were in
their answers. In order for a
wrong answer to be deemed a misconception, the student must have some
confidence in their incorrect answer and not be guessing. In this paper, the authors present a
study on the usefulness and gender-neutrality of implicit confidence tests --
tests used with multiple-choice assessment to measure students' confidence in
their understanding. They provide
substantial background about misconceptions and include their logic for using
the two-dimensional tests (TDTs). The
focus of this research was to test this method for gender bias. Previous research has indicated that
female students are naturally less confident in their opinion, so they compared
the number of times students of each gender indicated they were
"confident", "semi-confident" or guessing on the TDT. Their results indicate there is no difference
in the selection rate of those options between the genders.

I did not know about this paper until I read Jenny
Knight's bibliography, so I want to give her full credit for finding this
resource! As I create assessment
tools this paper seemed important to include as it directly addresses the
over-diagnosis of "misconceptions" (AKA "alternative
conceptions") in education. I
agree with the authors when they describe multiple-choice tests as creating the
illusion of misconceptions that do not actually exist. To test this hypothesis, they
administered a multiple-choice physics exam to 48 students and selected 9
students for a follow-up interview to more deeply explore their understanding
of the material.In their results,
23.5% of all "misconceptions" are false positives, meaning students
answered the question incorrectly on the written exam, but demonstrated
sufficient understanding during the interview. An average of 16% of the incorrect answers to the physics
questions they raised revealed true misconceptions; that is questions that were
answered incorrectly on the written exam and again in the interview. This study emphasizes the importance of
creating discerning assessment tools and using multiple methods to measure
student understanding.